Issue with RAM on 970A-UD3P failing to boot.

[Vicousvern]

Hello, recently I built a new pc and after looking through the bios it appears my RAM isn't running at its advertised speed. It should be 1866Mhz but in the bios is 1334Mhz. If I enable the XMP profile which sets it to 1866 I get a boot failure. The PC does work but, I'd be nice to have the speeds it should.

My specs are:
Gigabyte 970A-UD3P - Official Specs
AMD FX-8350
4 x 4Gb Crucial Ballistix Tactical Tracer - Ebuyer
GTX 770

According to the board specs it says it should be able to run them, so I'm not sure whats going on. Any help would be appreciated, or if this speed is correct and its just me I apologise.

 

[damric]

Often the Intel XMP profiles will not work with AMD CPUs due to weaker memory controller. You may just need to bump DRAM voltage a bit, and CPU-NB voltage a bit. Or, worse case scenario you may have to run at 1600MT/s or with looser timings.

 

[hovo1981]

Hi Vicousvern,

I beleive DIMM slot 3 and 4 are designed for memory speed up to 1866 mhz on some gigabyte boards.
You can try to populate only DIMM 3 and 4, ( 2 X 4GB ), configure the speed in bios and see if you can BOOT.

Regards,
Hovo

 

[Vicousvern]

Hi Vicousvern,

I beleive DIMM slot 3 and 4 are designed for memory speed up to 1866 mhz on some gigabyte boards.
You can try to populate only DIMM 3 and 4, ( 2 X 4GB ), configure the speed in bios and see if you can BOOT.

Regards,
Hovo

Ok, it Boots up with the sticks as advised and is working with the XMP profile. I have 2 questions now then: Will it work with all 4 sticks like this now? If not what would you recommend, 4 @ 1334 or 2 @ 1866? Thanks

 

[damric]

For system RAM More is usually better than fast.

 

[Vicousvern]

For system RAM More is usually better than fast.

Thanks, I tried your suggestion beforehand and it wouldn't boot at all, had to unplug my HDD to even get the Bios screen to show, was a tad worried!

 

[damric]

Memory tuning on AMD platform can be a bear.

 

[hovo1981]

Hi Vicousvern,

If it was me, I would actually leave 2 X 4GB running 1866mhz. or you can try to run 4 memory sticks, at 1600 mhz instead of 1866. Maybe you can lower the Latency, ex: from 9 to 8.

Good Luck
Hovo

Hi Vicousvern,

I beleive DIMM slot 3 and 4 are designed for memory speed up to 1866 mhz on some gigabyte boards.
You can try to populate only DIMM 3 and 4, ( 2 X 4GB ), configure the speed in bios and see if you can BOOT.

Regards,
Hovo

Ok, it Boots up with the sticks as advised and is working with the XMP profile. I have 2 questions now then: Will it work with all 4 sticks like this now? If not what would you recommend, 4 @ 1334 or 2 @ 1866? Thanks

 

[Vicousvern]

Hi Vicousvern,

If it was me, I would actually leave 2 X 4GB running 1866mhz. or you can try to run 4 memory sticks, at 1600 mhz instead of 1866. Maybe you can lower the Latency, ex: from 9 to 8.

Good Luck
Hovo

I tried 2 and 4 at 1600Mhz and the PC doesn't boot at all, just blank with no post. I've contacted Gigabyte see if they have any advice as well on the matter.
Either way it looks as if I can run 8Gb at 1866Mhz or 16gb at 1334Mhz but I'm torn on what to choose as I mostly game. Thinking the more the better, cant see there being a huge difference in performance. Regardless thanks for the responses, and if Gigabyte get back I'll let you guys know.

 

[damric]

Hi Vicousvern,

If it was me, I would actually leave 2 X 4GB running 1866mhz. or you can try to run 4 memory sticks, at 1600 mhz instead of 1866. Maybe you can lower the Latency, ex: from 9 to 8.

Good Luck
Hovo

I tried 2 and 4 at 1600Mhz and the PC doesn't boot at all, just blank with no post. I've contacted Gigabyte see if they have any advice as well on the matter.
Either way it looks as if I can run 8Gb at 1866Mhz or 16gb at 1334Mhz but I'm torn on what to choose as I mostly game. Thinking the more the better, cant see there being a huge difference in performance. Regardless thanks for the responses, and if Gigabyte get back I'll let you guys know.

You can run at 1333 and tighten down timings and it should still be quite fast., Default JEDEC timings for DDR3-1333 are 9-9-9-24. An ultimate goal is 6-6-6-18 but usually 7-7-7-21 is what most end up with. Be ready for many CMOS Clears when tuning timings

 

[Vicousvern]

Hi Vicousvern,

If it was me, I would actually leave 2 X 4GB running 1866mhz. or you can try to run 4 memory sticks, at 1600 mhz instead of 1866. Maybe you can lower the Latency, ex: from 9 to 8.

Good Luck
Hovo

I tried 2 and 4 at 1600Mhz and the PC doesn't boot at all, just blank with no post. I've contacted Gigabyte see if they have any advice as well on the matter.
Either way it looks as if I can run 8Gb at 1866Mhz or 16gb at 1334Mhz but I'm torn on what to choose as I mostly game. Thinking the more the better, cant see there being a huge difference in performance. Regardless thanks for the responses, and if Gigabyte get back I'll let you guys know.

You can run at 1333 and tighten down timings and it should still be quite fast., Default JEDEC timings for DDR3-1333 are 9-9-9-24. An ultimate goal is 6-6-6-18 but usually 7-7-7-21 is what most end up with. Be ready for many CMOS Clears when tuning timings

Cheers, it's an option to have a go at once I've read up on it.

Gigabyte got back to me, here's they're response: "That's the AMD limitation. Only one DIMM per channel is supported for DDR3-1866MHz and higher speed as using an AM3+ CPU."

Seems a bit silly in my opinion, don't suppuse there's a board that does support 2 DIMMs at 1866 on both channels? I rarely go for Gigabyte but thought I'd give it a whirl this build, if its simply a gigabyte limitation then I'll be a bit disappointed.

So yea, any mobo recommendations would be appreciated else I'll resort to tightening the timings as damric suggested.

 

[hovo1981]

Hi again,

So Gigabyte is telling you, you can only run 2 DIMMS at 1866mhz. I have a gigabyte board also, the owner manual mentions only DIMM 3 and 4 can be used for 1866mhz, Im guessing the motherboard you have is the same. I think it maybe its a BIOS or a AM3+ limitation.

I know Asus is a very good with Motherboards. You can go with ASUS, with 990X or 990FX chipsets.

Regrads,
Hovo

Hi Vicousvern,

If it was me, I would actually leave 2 X 4GB running 1866mhz. or you can try to run 4 memory sticks, at 1600 mhz instead of 1866. Maybe you can lower the Latency, ex: from 9 to 8.

Good Luck
Hovo

I tried 2 and 4 at 1600Mhz and the PC doesn't boot at all, just blank with no post. I've contacted Gigabyte see if they have any advice as well on the matter.
Either way it looks as if I can run 8Gb at 1866Mhz or 16gb at 1334Mhz but I'm torn on what to choose as I mostly game. Thinking the more the better, cant see there being a huge difference in performance. Regardless thanks for the responses, and if Gigabyte get back I'll let you guys know.

You can run at 1333 and tighten down timings and it should still be quite fast., Default JEDEC timings for DDR3-1333 are 9-9-9-24. An ultimate goal is 6-6-6-18 but usually 7-7-7-21 is what most end up with. Be ready for many CMOS Clears when tuning timings

Cheers, it's an option to have a go at once I've read up on it.

Gigabyte got back to me, here's they're response: "That's the AMD limitation. Only one DIMM per channel is supported for DDR3-1866MHz and higher speed as using an AM3+ CPU."

Seems a bit silly in my opinion, don't suppuse there's a board that does support 2 DIMMs at 1866 on both channels? I rarely go for Gigabyte but thought I'd give it a whirl this build, if its simply a gigabyte limitation then I'll be a bit disappointed.

So yea, any mobo recommendations would be appreciated else I'll resort to tightening the timings as damric suggested.

 

[damric]

It's not a limitation imposed by the motherboard. It is a limitation of the weak memory controller on the AMD CPU. The motherboard's only job is to automatically detect speed tables and set accordingly when things are left in automatic.

 

[Vicousvern]

It's not a limitation imposed by the motherboard. It is a limitation of the weak memory controller on the AMD CPU. The motherboard's only job is to automatically detect speed tables and set accordingly when things are left in automatic.

So regardless of brand the use of 4 sticks at 1866 is impossible due to the CPU? I don't understand why this isn't mentioned anywhere, if I knew this I wouldn't have bought 4 sticks. In fact all it says on numerous specs sheets for the board is that its compatible with higher and speeds and up to 32Gb.

I presume 4 sticks at a lower speeds such as 1600 should be compatible then? Again presuming that AMD is only incompatible past 1866. However when I set the modifier in my bios so it runs at 1600 it didn't boot at all or is this because I didn't set the proper tRAS, tRC and voltage values to reflect this? Apologies but I'm new to tweaking memory, from past experiences it just works straight out of the box.

Should I just deal with it and trim the timings of 4 sticks @ 1334? Or try and get 1600 working with 4 sticks, not entirely sure what the AMD limitations are at this point. Cheers for all the advise so far by the way, very informative!

 

[damric]

It's not a limitation imposed by the motherboard. It is a limitation of the weak memory controller on the AMD CPU. The motherboard's only job is to automatically detect speed tables and set accordingly when things are left in automatic.

So regardless of brand the use of 4 sticks at 1866 is impossible due to the CPU? I don't understand why this isn't mentioned anywhere, if I knew this I wouldn't have bought 4 sticks. In fact all it says on numerous specs sheets for the board is that its compatible with higher and speeds and up to 32Gb.

I presume 4 sticks at a lower speeds such as 1600 should be compatible then? Again presuming that AMD is only incompatible past 1866. However when I set the modifier in my bios so it runs at 1600 it didn't boot at all or is this because I didn't set the proper tRAS, tRC and voltage values to reflect this? Apologies but I'm new to tweaking memory, from past experiences it just works straight out of the box.

Should I just deal with it and trim the timings of 4 sticks @ 1334? Or try and get 1600 working with 4 sticks, not entirely sure what the AMD limitations are at this point. Cheers for all the advise so far by the way, very informative!

The Spec Sheets and QVLs that (especially motherboard manufacturers) put out are filled with many misleading half-truths. When FX CPUs were first released, AMD spec'd its memory controller to be able to run two dimms at DDR3-1866. They did not say what timings, voltage, or density. Overclockers such as myself know that it's possible to exceed those specs, and motherboard manufacturers often outright lie on QVLs. A mobo manufacturer might advertsise something like DDR3-2600 (OC). For all you know that could be just one 1GB module at some very loose timings. Then you have memory manufacturers themselves rating RAM to run at certain specs when the XMP profile is enabled. XMP is only guaranteed to work on Intel CPUs. Sometimes the XMP profile works on AMD platform, sometimes it doesn't. AMD used to have something similar called Black Edition Memory Profile, but it never caught on because memory and motherboard makers apparantly couldn't be bothered. Now AMD has its own Radeon branded RAM which has an AMD Memory profile that is guaranteed to work at rated specs. Too bad they are more expensive and lower performance (often costs more with loose timings). Oh and only a few motherboard makers like ASRock even adopted AMP. It's quite a cluster----.

Ranting aside, it is possible with some overclocking (pushing voltages and such a bit out of spec) to get some good RAM speeds on AMD platform. I'm running 2x4GB of DDR3-2400CL10 myself on an Athlon.

 

[Vicousvern]

Makes sense now thank you for taking the time to explain. To wrap things up whats your opinion:

• 
  ■ Lower the timings of 4 sticks @ 1334?
  ■ Or run 4 sticks @ 1600, or is this also impossible?

Thank you and it's very much appreciated.

 

[damric]

If you have the patience, I bet you can get them running at 1866. I'd start by trying 1600 though. Be ready for some CMOS Clears if it becomes so unstable that it does not boot.

I managed to get 16GB of mixed RAM kits running at 1800CL7 and one of the kits was only rated 1600CL9 and this was on an FX-4100 with weaker memory controller.

You can try some of my settings:

http://www.gskill.us/forum/showthread.php?t=10657

 

[Vicousvern]

Quick update: I managed to get 4 sticks running at 1600. All I did was enable the XMP profile but lower the multiplier to 1600 instead of 1866.

So now its running @ 1600CL8.

I tried lower timings and testing the results in MaxxMem2 but anything below 8-8-8-23-32 @1T I got < 9.50Gbps, highest was 10.30Gbps. I even used your values in that other thread but they didn't work that fast or am I testing this wrong? I got as far as testing up to 1600CL6 but it wont post.
Any suggestions on what to try to get it faster or even if I'm testing it wrong let me know please. Thanks!

 

[damric]

1600CL8 is pretty good for 16GB on AMD.

 

[Vicousvern]

Great. Am I right in going of the overall reached memory score? Because it fluctuates between 9.00 to 10.40Gbps quite often. I tried plenty of lower timing combinations all to no avail 8-8-8-23 seems to be the highest scoring. Unless of course I'm missing something I can give you a screenshot of my AMD Overdrive settings but from what I can see there isn't much else to edit.
I'm sure I had it higher but wasn't note taking at the time.

 

[damric]

AIDA 64 and Sandra have more consistent memory benchmarks. MaxxMem is very flaky.

But yeah you are on par. Above average even.

 

[Vicousvern]

Tried AIDA 64 on both 1600CL7 / CL8 and it looks as if its slightly faster at CL7 using 7-7-7-20 30 1T. Is it worth trying to get any more out of this? Because it wouldn't post at CL6 so I'm not sure if there is anymore room for improvement.

CL7:

CL8:

At any rate I'm really happy with the results so far, especially since its my first time doing it, surprised at how easy it is. So yea, would appreciate your opinion on what to do, I think CL7 is a bit faster but I also think its the best I'm going to manage.

 

[damric]

Keep tuning until you run out of patience. You see how it goes, tightening one at a time and testing for stability. Most people don't mess with it. I like pushing the envelop though

1600CL7 is freaking fast for 16GB on AMD.

 

[damric]

Here's mine, but only 2x4GB

 

[Vicousvern]

Nice, guessing you have better quality ram than I do! I definitely know I can't boot when its 1600CL6 but I guessing I can at least try 7-6-6-20 or lower, not sure how it will handle. Any rate I'll test this tomorrow and keep you informed, cheers for all the help / advice so far.